Modification of polished silicon under exposure to radiation of nanosecond ultraviolet laser

Abstract

The polished surface of monocrystalline silicon was exposed to radiation of nanosecond ultraviolet laser (λ = 355 nm, pulse duration - 10 ns, pulse energy - up to 8 mJ, pulse repetition rate - up to 100 Hz). Then the samples were examined by scanning electron microscopy and multibeam optical profilometry. The optical damage threshold accompanied by the appearance of a plasma torch near the surface and crater formation was 1.2 J/cm2. Microbreakdown centers on processing defects were observed at an energy density more than 0.2 J/cm2. In the range 0.2 - 1.2 J/cm2 traces of surface lifting were observed.